More than 11 months after the first disclosure was made, ACT Health decided earlier in October that four of the complaints might amount to disclosable conduct and would be investigated further.

In a letter to one of the doctors, Canberra Health Services chief executive Bernadette McDonald confirmed that claims of inappropriate Medicare billing and breast imaging being done without radiologist supervision were being investigated further, after an independent lawyer conducted a preliminary investigation. Ms McDonald also acknowledged the delay in dealing with the disclosure.

The Australian Medical Association said the length of time it had taken ACT Health to deal with the complaints showed serious issues around its processes, while the opposition has renewed its calls for a board of inquiry to protect whistleblowers.

The three disclosures by three radiologists, submitted in November 2017 and February this year, are now being treated by the government as one disclosure.

The first disclosure was made by a doctor on November 3, 2017, alleging "maladministration" in the medical imaging department.

ACT Health deputy director general Chris Bone was sent a disclosure in early November about work practices in the medical imaging department during the recruitment of director of medical imaging Mark Duggan, emails obtained via freedom of information reveal.

Mr Duggan was acting manager of medical imaging at the time.

In the disclosure, submitted to Dr Bone on November 3, the whistleblower doctor alleged mammography examinations were being performed without radiologist supervision and then improperly billed to Medicare, according to freedom of information documents.

The doctor who made the disclosure said in an email obtained via freedom of information that he/she had followed up with Mr Bone by phone and email after sending the disclosure.

The author of the disclosure also claimed Mr Bone had been made aware of it through discussions with a lawyer in November.

But in an email to the public standards unit, Mr Bone said he had not read the original disclosure, which was sent on November 3 until December 22, as it was in his spam folder.

He also said the lawyer had not indicated a disclosure had been submitted.

"I acknowledge that in this instance this matter did not occupy the priority for me that it should have given the circumstances I am aware of now," Mr Bone said in an email to the public standards unit.

The disclosure was made during the recruitment for the role Mr Duggan is now in, and months before other doctors made a disclosure in February about the alleged manipulation of the recruitment process in favour of Mr Duggan.

Mr Duggan was acting manager of medical imaging in 2017, before he was appointed to the newly created executive position of director of medical imaging in February 2018.

He was appointed by a three-member recruitment panel that initially included ACT Health deputy director general Chris Bone and then chief medical officer Jeffrey Fletcher (Dr Fletcher resigned this week, telling colleagues he would be looking for jobs outside of Canberra).

Documents show Mr Bone and Dr Fletcher ranked Mr Duggan as their preferred candidate, despite him having no formal qualifications and another candidate with more experience and qualifications applying.

There is no suggestion that Mr Duggan was unable to properly perform his role or at any time posed a risk to patients. Mr Duggan maintains he has at all times been appropriately skilled to carry out his role. He strenuously denies having been unqualified for his job or undeserving of it, and The Canberra Times makes no such allegations against him.

Through his lawyers, Aulich Civil Law, Mr Duggan has said he believes there has been a campaign against him, and he is considering seeking an order from the Fair Work Commission to stop bullying or, alternatively, instituting Federal Court proceedings alleging civil conspiracy to damage his economic interests.

Correspondence from the Australian Medical Association showed since the disclosures were made by the doctors, six preliminary assessments have been directed to the doctors concerned.

A preliminary assessment is made when a staff member is accused of misconduct, and a decision is made whether to investigate.

Freedom of information documents reveal the doctor who made the initial disclosure about breast imaging practices was then accused of misconduct by ACT Health, and as of February 14 had not heard anything about the status of the disclosure.

The doctor said he/she believed ACT Health knew about the disclosure and then began a preliminary assessment on him/her.

One doctor also lost their senior role in the hospital after the disclosure was made.

The disclosures came before a scathing report from the Royal Australian and New Zealand College of Radiologists in March. It dropped the Canberra Hospital's radiology training ranking from an A to a D.

The assessors noted the most significant issue facing the hospital's medical imaging department was the negative environment in the department.

They also noted a lack of clinical control over the department, with the clinical leaders having minimal involvement with the recruitment of new trainees, rostering of the clinical staff and other significant departmental decisions.

The disclosure made in February was provided to The Canberra Times by one of the radiologists after receiving legal advice ACT Health had not complied with statuary regulations about dealing with disclosures within a certain timeframe and therefore the could be passed on to a journalist and a member of parliament.

Questions to Mr Bone, Dr Fletcher, ACT Health and Ms Fitzharris all went unanswered.

A spokesman for Canberra Health Services said it was legally unable to answer questions under the Public Interest Disclosure Act 2012.

Australian Medical Association ACT president Antionio Di Dio said the association had been helping members for some time with several complaints relating to the medical imaging department.

“The recent letter from ACT Health responding to the complaints made by one of the radiologists is significant because it finds that four of the complaints may amount to serious misconduct, maladministration or breaches of the law," he said.

Dr Di Dio said it was important complaints were dealt with fairly, fully and in a timely manner for doctors to have confidence to make them.

"In this case, ACT Health has taken eleven months to determine that the allegations may be ‘disclosable conduct’," he said.

“Given that it is only now the main investigation of the complaints may take place, this is far too long and indicates serious issues around ACT Health’s own processes.

“I’d urge ACT Health to get on with the main investigation as soon as possible. Anything else risks further undermining confidence in the process and increasing the uncertainty for all concerned.”

Mrs Dunne said the doctor who made the serious allegations must be protected, as the law required.

“The whistleblower followed a legal process to bring to light what they allege to be wrongdoing," she said.

“The whistleblower subsequently revealed their concerns to me and later to the media as is their right under the law.

"I have also raised the issue of the filling of this position in the Legislative Assembly on August 15, 2018, but Health Minister Meegan Fitzharris failed to respond.

“The matter was only reported in the media after the government failed to respond to the disclosure according to the law."

Mrs Dunne said if the allegations were true, they further demonstrated the "deeply troubling" issues in the health system, renewing her calls for a board of inquiry into ACT Health.

She said the independent review announced by the government in September did not provide a satisfactory legal framework to protect witnesses and panel members who may make an adverse finding.